SummaryMultivalency effects are essential in carbohydrate recognition processes as occurring on the cell surface. Thus many synthetic multivalent glycoconjugates have been developed as important tools for glycobiological research. We are expanding this collection of molecules by the introduction of carbohydrate-scaffolded divalent glycothymine derivatives that can be intramolecularily dimerized by [2 + 2] photocycloaddition. Thus, thymine functions as a control element that allows to restrict the conformational flexibility of the scaffolded sugar ligands and thus to “organize” multivalency. With this work we add a parameter to multivalency studies additional to valency.

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Carbohydrates serve as versatile molecular scaffolds and platforms in organic chemistry, for example in combinatorial chemistry or for the multivalent presentation of ligands. Carbohydrate scaffolds are frequently employed in the synthesis of multivalent glycoconjugates and utilized for the study of fundamental parameters of carbohydrate recognition. However, facile procedures are required to achieve a useful variety of sugar platforms. Here, we report on the synthesis of a series of divalent und tetravalent hydroxypropylated mannosides, using an allylation‐hydroboration sequence. The hydroxypropyl‐linkers were further functionalized with thymine in a Mitsunobu reaction to achieve multivalent glycothymine scaffolds for intramolecular [2+2] photocyclization. This will be of importance to further investigate the influence of the 3D orientation in carbohydrate recognition. We discuss the scope of the allylation‐hydroboration sequence comparing 2,3‐, 2,6‐, and 4,6‐difunctionalization and 2,3,4,6‐tetrafunctionalization of protected 2‐aminoethyl α‐d‐mannopyranosides.